Process of reducing ores.



UNITED STATES PATENT OFFICE.

HENRY ARDEN, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR TO JOHN TREADIVELL,OF OAKLAND, CALIFORNIA.

PROCESS OF REDUCING ORES.

Specification of Letters Patent.

Patented Oct. 3, 1905.

Application filed April 21, 1903. Renewed May 31, 1905. Serial No.263.153.

To all whom it may concern: Be it known that I, HENRY ARDEN, a citizenof the United States, residing at San Francisco, California, haveinvented a certain new and useful Process of Reducing Ores, of which thefollowing is a specification.

This invention is more especially applicable to the reduction offinely-comminuted or sand ore.

I mix crude petroleum or any of its less volatile fractions withwater-glass in solution. \Vith this I put finely-pulverized coal orlignite, or the dust thereof, and the finely-divided ore or sand to bereduced. I then form this mass into briquets or other forms and placethem in an oven or furnace, where they are subjected to combustion,preferably slow combustion. The effect of this combustion is theformation of a coke which holds together the particles of the ore and atthe same time produces a partial reduction of the ore, (if the relativetemperatures of the burning mass and the heat of dissociation of the orepermit.) When coked as aforesaid, the mass is subjected to a strongerheat, with the addition of the necessary fluxes and more carbon, ifnecessary, either in the same furnace or in another suitable furnace towhich it is removed and the reduction completed. The proportions when mycarbon is a lignite of about forty per cent. carbon and my ore magnetiteare: equal portions, by Weight, of the lignite and ore; relativeproportions of waterglass to the hydrocarbon, one to three or one tofour, with enough water to dissolve the water-glass to about theconsistency of the hydrocarbon. These are mixed together and added tothe coal and ore in sufiicient quantity to make the mass the properconsistency to form the briquets. The above proportions can be variedwithin wide ranges, depending on the nature of the hydrocarbon, thenature of the coal or lignite, and the nature of the ore, or of any twoor all of them.

My process is very applicable to the new method, whereby the sulfide ofmetal are separated by oil from the gangue and oxids of metals. Afterthe oil has become loaded with the sulfid, instead of separating the oiland sulfid by centrifugal or other means, as now done, I use the same(oil and sulfids) as mixed as part of the ingredients of my briquet.

The use of a hydrocarbon and water-glass in combination is essential tothe best results in the production of an ore briquet. A briquetconsisting of ore, coal, and petroleum would not retain its form whensubjected to moderately high temperatures much below those at which thereduced metal melts. The heated briquets would become soft and wouldcrumble under the pressure of the load in the furnace. Furthermore, thebriquet without water-glass evolves much smoke, which burns with ayellowish flame. The water-glass practically prevents the evolution ofsmoke, and the flame is white and not so voluminous. It is probable thatthe water-glass is decomposed under the effect of the heat and thecarbon dioxid in the products of combustion, forming sodium carbonateand silicic acid, the latter changing to a thin covering of silica. Theadvantage arising from the use of water-glass in ore briquets is suchthat its cost may be neglected.

l/Vhat I claim, and desire to obtain Letters Patent for, is

1. The herein-described method of briqueting finely-divided ores whichconsists in mixing with the same carbonaceous matter, a hydrocarbon, andwater-glass, and forming the mixture into coherent masses, substantiallyas described.

2. The herein-described method of briqueting finely-divided ores whichconsists in mixing with the same carbonaceous matter, a hydrocarbon, andwater-glass, forming the mixture into coherent masses, and coking saidmasses, substantially as described.

3. The herein-described method of reducing finely-divided ores whichconsists in mixing with said ores carbonaceous matter, a hydrocarbon,and water-glass, forming the mixture into coherent masses, coking saidmasses, and finally reducing the ores, substantially as described.

4. A briquet containing finely-divided ores, carbonaceous matter, ahydrocarbon, and water-glass, substantially as described.

5. A briquet containing finely-divided ores, carbonaceous matter, theless volatile fractions of crude petroleum, and water-glass,substantially as described.

HENRY ARDEN.

Witnesses:

NAT. M. RAPHAEL, T. A. PAGE.

